Heated handle and method of forming same

ABSTRACT

A heated handle (e.g. a steering wheel) is provided for an article of manufacture such as an automotive vehicle along with a method for forming the handle. The handle typically includes a core, an outer cover layer and a heater, which is preferably disposed at least partially between the outer cover layer and the core. The heater typically includes one or more of a conductor, a cushion and a separator.

FIELD OF THE INVENTION

The present invention relates generally to heated handles and moreparticularly to heated steering handles (e.g., steering wheels) for usein automotive vehicles.

BACKGROUND OF THE INVENTION

For many years, industry has been concerned with designing improvedhandles for use in transportation vehicles or elsewhere and has beenparticularly concerned with designing improved steering wheels forautomotive vehicles. As examples, U.S. Pat. Nos. 6,172,342, 6,093,908are directed toward advancements in designs for steering wheels ofautomotive vehicles. In the interest of continuing such innovation, thepresent invention provides a heatable handle, which may be suitable forvarious transportation vehicles or other uses, but which has foundparticular utility as a heatable steering wheel for an automotivevehicle.

SUMMARY OF THE INVENTION

According to the present invention, there is disclosed a handle, whichmay be used for steering a transportation vehicle. The handle typicallyincludes a heater and the heater is preferably positioned at leastpartially between a core and an outer covering of the handle. The heatertypically includes one or more of a cushion, a separator, and aconductor and the conductor is preferably disposed at least partiallybetween the cushion and the separator. In a preferred embodiment, thecore is relatively rigid and is at least partially covered with asynthetic covering and has a substantially circular configuration.Optionally the core is designed to include one or more stressconcentrators or relievers for controlled deformation in the even toextreme load conditions. Also in the preferred embodiment, the outercovering is formed of a grippable synthetic material such as leather,wood, metal, carbon fiber or a combination thereof and substantiallyentirely covers the core. The cushion is preferably provided as a layerof foamed or unfoamed plastic material, and more preferably one havingat least one elastomer. The separator is preferably provided as a wovenor unwoven fabric layer that is substantially coextensive with thecushion. The conductor is preferably at least partially between thecushion and the separator.

BRIEF DESCRIPTION OF THE DRAWINGS

The features and inventive aspects of the present invention will becomemore apparent upon reading the following detailed description, claimsand drawings, of which the following is a brief description:

FIG. 1 is a perspective view of an internal portion of an automotivevehicle having an exemplary steering handle in accordance with thepresent invention;

FIG. 2 is an exploded perspective view of the exemplary steering handleof FIG. 1;

FIG. 3 is an elevational view of an exemplary heater in accordance withthe present invention;

FIG. 4 is an exploded sectional view of the exemplary heater of FIG. 3taken along line 4—4; and

FIG. 5 is a sectional assembled view of the exemplary heater of FIG. 3taken along line 4—4.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is predicated upon providing an improved steeringhandle. It is contemplated that the handle may be employed in a varietyof transportation vehicles including, without limitation, busses, boats,trains, tractors, motorcycles, airplanes, bicycles or the like. It isalso contemplated that the heated handle may be employed in a variety ofother environments such as within buildings, outdoors or the like. As anexample, the heated handle may be configured as a grip for articles suchas ski poles, walkers, hand tools or the like. As other examples, theheated handle may be configured as a stair or other railing, a doorhandle or the like. It has been found, however, that the handle isparticularly effective when configured as a steering wheel of anautomotive vehicle.

According to one aspect of the invention, the handle includes animproved heater for warming the handle. The improved heater, the handleor both may provide one or more of a variety of advantages inconstruction, durability, performance, assembly or the like. As oneexample, the heater may be formed of materials that allow the heater tobe easily assembled as part of the handle. As another example, a moreefficient method of formation of the heater may be employed according tothe present invention. Other advantages of the present invention willbecome apparent from the following description.

Referring to FIGS. 1 and 2, there is illustrated a handle, and moreparticularly, a steering handle 10 in accordance with an aspect of thepresent invention. The steering handle 10 is illustrated in a preferredconfiguration (i.e., as a steering wheel of an automotive vehicle). Itshall be understood, however, that a handle according to the presentinvention may be formed in a variety of configurations.

Typically, the handle 10 includes a core 12 an outer covering 14 and aheater 16 that is preferably positioned substantially between the core12 and the covering 14 although not necessarily required. The heater 16is generally composed of at least one thermal conductor, and may includeadditional components, such as a component for attaching the heater tothe core, a component for providing a cushion, a separator, combinationsthereof or the like.

Referring to FIGS. 3-5, one preferred exemplary heater 16 is illustratedaccording to the present invention. The heater 16 includes a conductor24, a cushion 26 and a separator 30. In the exemplary embodimentillustrated, the conductor 24, the cushion 26, and the separator 30 areeach illustrated as layers, which are laminated together. In thepreferred embodiment, the conductor 24 is positioned substantiallyentirely between the separator 30 and the cushion 26, however, inalternative embodiments, the conductor 24 may be partially or fullyoutside of one or both of the separator 30 and the cushion 26.

The conductor 24 may be comprised of one singular continuous conductiveelement or a plurality of conductive elements. The conductor 24 may alsobe comprised of one singular continuous conductive element that isdivided into a plurality of conductive zones. Additionally, theconductive element[s] of the conductor layer 24 may be provided inseveral configurations such as one or more wires, strips, tapes, bands,combinations thereof or the like. In the particular embodimentillustrated, the conductor 24 includes one singular continuousconductive element 36 divided into three conductive zones 38 (e.g.,circuits) and the conductive element 36 is formed of a plurality (e.g.,about 3 to about 9, more preferably about 5 to about 7) of copper wirestrands, which may be woven together. Preferably the strands each have adiameter between about 0.004 mm or less and about 0.02 mm or greater,more preferably between about 0.007 mm and about 0.011 mm and still morepreferably between about 0.008 mm and about 0.009 mm.

It is contemplated that the conductor 24 may be partially or completelyformed of several different conductive materials such as metals,conductive polymers, polymers with conductive dispersions, fluidicmaterials, combinations thereof or the like. In the preferredembodiment, the conductive element[s] 36 are formed of copper, nickel orcombinations thereof. For example, the conductive element[s] can includeup to 15% by weight nickel or greater and preferably is an alloy thatincludes between about 0.01% and about 13% by weight nickel and morepreferably includes between about 0.1% and about 11% by weight nickeland even more preferably includes between about 1% and about 10% (e.g.,about 2%) by weight nickel. It is also preferable for the conductiveelement to exhibit a resistance between about 0.01 Ω/m or less to about5.0 Ω/m or greater, more preferably about 0.7 Ω/m to about 4.0 Ω/m andstill more preferably about 1.5 Ω/m to about 2.5 Ω/m.

The cushion 26 may be provided in a variety of shapes andconfigurations. As examples, the cushion 26 may be flat, contoured,cylindrical, geometric, continuous, non-continuous, combinations thereofor the like. Alternatively, the cushion 26 may be located in only selectlocations of the handle 10 the heater 16 or both. In the depictedembodiment, the cushion 26 is illustrated a substantially continuouslayer or elongated strip having a substantially uniform thickness.

Many various materials may form part or all of the cushion 26. Exemplarymaterials include fabrics, rubbers, foams, polymeric materials such aselastomers and plastomers, spunfibers, gels, air bladders, combinationsthereof or the like. In the preferred embodiment illustrated, thecushion 26 is provided as an extruded, molded, cut, or otherwise formedlayer of polymeric foam. The skilled artisan will recognize that amyriad of polymeric foams may be employed in the present invention.Examples of particularly preferred materials for the cushion 26 includefoams that include or are formed of elastomer (e.g., neoprene),polyurethane, polyvinylchloride, polyol combinations thereof or thelike. In one particularly preferred embodiment, the cushion 26 is formedof a flexible, stretchable, compressed polyurethane foam sold underProduct Number: A300135 and commercially available from FoamexInternational Inc., 1000 Columbia Avenue, Linwood, Pa. 19061.

The material for the cushion is one that preferably has an elongationcharacteristic permitting it to be deformed (i.e., elongated) at leastabout 10%, more preferably about 25%, even more preferably about 50% andstill more preferably about 75% of its own length prior to failure(e.g., rupture). Moreover, the material for the cushion is generally aninsulator material that has a heat transfer coefficient between about0.001 W/mK or lower and about 0.500 W/mK or higher, more preferablybetween about 0.005 W/mK and about 0.200 W/mK, and even more preferablybetween about 0.010 W/mK and about 0.100 W/mK. The thickness of thecushion is preferably between about 0.5 mm or less to about 3 mm orgreater and more preferably between about 1 mm and about 2 mm.

The separator 30 may be formed in several shapes, sizes andconfigurations. For example, the separator may be continuous orintermittent, may have variable or substantially continuous thickness ormay be otherwise configured as desired for a chosen application.Preferably, for the heater 16 shown, the separator 30 is configured tobe substantially coextensive with the cushion 26. In FIGS. 3-5, theseparator 30 is provided as a layer (e.g., an elongated strip) thatsubstantially mirrors the cushion 26.

It is contemplated that the separator 30 may be formed of any of thepotential materials suitable for the cushion 26 and the cushion 26 andthe separator 30 may be formed of the same or different materials. Inpreferred embodiments, the separator 30 is formed of a fabric material,a fibrous material, a woven material, an unwoven material, a flock, aroving, combinations thereof or the like. Exemplary preferred materialsinclude gauze, fleece, felt or the like. In one highly preferredembodiment, the separator is provided as a layer that is flexible,stretchable or both.

A highly preferred separator is a fleece formed of polymeric materialssuch as polyester, polyobfin (e.g. polypropylene), polyamidecombinations thereof or the like. Moreover, the preferred material hasan elongation characteristic permitting it to be deformed (e.g.,stretched or elongated) at least about 10%, more preferably about 25%,even more preferably about 50% and still more preferably about 75% ofits own length prior to failure (e.g., rupture). Additionally, thematerial for the separator preferably has a heat transfer coefficientbetween about 0.01 W/mK or lower and about 4.00 W/mK or higher, morepreferably between about 0.1 W/mK and about 2.00 W/mK, and even morepreferably between about 0.5 W/mK and about 1.00 W/mK. Preferably, theheat transfer coefficient of the separator 30 is higher than the heattransfer coefficient of the cushion 26. As an example, one particularlypreferred material for the separator 30 is apolyester/polypropylene/polyamide fleece material sold as part number:10660 or article number: EA-1111-A and commercially available from TWEVliesstoffwerke Gmblt & Co., Hollefeldstrasse 46, 48282 Emsdetten,Germany.

To assemble the heater 16, it is contemplated that two or more of thecushion 26, the conductor 24 and the separator 30 may be configured inany order or position relative to each other. Preferably, however, theconductor 24 is arranged in a lay-wire configuration between the cushion26 and the separator 30, all three of which are laminated in layers toeach other.

It is contemplated that assembly of the heater 16 includes attaching anytwo or more of the conductor 24, the cushion 26, and the separator 30 toeach other with one or more fasteners (e.g., adhesives, mechanicalfasteners or the like). Alternatively or additionally, the conductor 24,the cushion 26, and the separator 30 may self-attach or self-adhere toeach other. It is also contemplated that the conductor 24, the cushion26, and the separator 30 may be mechanically self-attached to each other(e.g., woven together) or may be self-adhered to each other by softeningor melting one of the conductor 24, the cushion 26, and the separator 30such that it can wet and adhere to another of the conductor 24, thecushion 26, and the separator 30 Alternatively, surface ingredients ofthe conductor 24, the cushion 26 or the separator 30 may be activated tointeract and bond the components together.

In the preferred embodiment, the cushion 26, the separator 30 or bothare respectively provided with first surface 44, 46 and adhesivecomponents 48, 50 (e.g., supplied as a layer, powder or otherwise)laminated, dispersed or otherwise placed on one, but preferably both ofthe first surfaces 44. 46. The conductive element 36 is pre-arranged inits desired pattern (e.g., by patterning the element about retractableposts). Thereafter, the conductive element 36 is arranged (e.g., lain)upon and/or attached (e.g., adhered) to one or both of the firstsurfaces 44, 46 of the cushion 26, the separator 30, the adhesivecomponents 48, 50 or a combination thereof. Optionally, the conductiveelement 36, the adhesive components 48, 50, the cushion 26, theseparator 30 or a combination thereof may be heated and pressed toassist in attaching the conductive elements 36 to one or more of thesecomponents. It is contemplated that the conductive element may beattached to the cushion 26 or separator 30 with the adhesive components48, 50 and/or additional fasteners (e.g., tape or the like).

As shown, the zones 38 of the conductive element 36 extend generallyparallel to each other in a zig-zag configuration. Also according to thepreferred embodiment, the separator 30 is attached (e.g., adhered) tothe cushion 26, the conductor 24 or both. Although various methods ofattachment may be employed, one preferred method includes hot laminating(e.g., with a belt laminator) the separator 30 to the cushion 26 withthe adhesive components 48, 50 (e.g., supplied as a layer, powder orotherwise) and the conductor 24 positioned therebetween. One preferredadhesive component is a multipurpose monolayer adhesive film sold underthe tradename Integral 899A commercially available from Dow ChemicalCorporation, Midland, Mich.

An electrical connection (e.g., an electrical harness) is typicallyemployed for electrically connecting the heater of the present inventionand particularly the conductor of the heater to a power source (notshown) of the automotive vehicle. A wide variety of electricalconnections may be adapted for use with the heater of the presentinvention.

In the illustrated embodiment, there is an electrical connection 58 thatincludes a plurality of conductors 60, a plug 62 for connecting to thepower source of the vehicle and a patch 64 (e.g., a tape patch). Forconnecting the electrical connection 58 to the conductor 24, one or moreopenings (not shown) are formed in the cushion 26 such that theconductive element 36 can extend through the cushion 26 to theconductors 60 of the connection 58. The conductive element 36 may beattached to the conductors 60 of the connection 58 by crimping,soldering or other technique and the conductors 60 may be insulated withelectrical tape, dielectric tubes (e.g., polymeric shrink tubes) or thelike. Preferably, a portion of the conductive element 36 is folded overonto itself and twisted at the connection 58 for lowering localizedresistance as the connection 58 thereby avoiding heat buildup. It isalso preferable for an opening 68 to be provided in the cushion 26 theconductors 60 may be attached to the conductive element 36.Advantageously, the opening 68 can provide additional space for avoidingread through of the connection 58 upon installation of the heater. Onceconnected, the patch 64 is applied or adhered to the cushion 26, theconnection 58 or both for assisting in securing the connection 58 inplace.

It is contemplated that the shape of the heater 16 may be differentdepending upon the article to which the heater 16 is applied and otherfactors as well. For the embodiment illustrated wherein the heater 16 isto be applied within the steering handle 10, the heater 16 is formed asa layer of an elongated strip with a slight curvature along a length ofthe strip. The heater also includes a plurality of protrusions 66 spacedapart along the length of the strip. Preferably, the protrusions 66correspond to spokes 72 of the steering handle 10. For shaping theheater 16, the components 24, 26, 30 may be supplied and assembled intheir final desired shape or may be assembled followed by cutting (e.g.,die cutting) or otherwise shaping the heater 16.

The heater of the present invention may be integrated with a handle orwith another article of manufacture as a singular assembled unit orseparately in components. Moreover, the heater may be attached to anarticle using various fasteners such as mechanical fasteners, adhesivesor the like. Alternatively, portions of the heater may physically ormechanically attach to an article of manufacture or an article ofmanufacture may physically or mechanically attach to the heater.

The heater 16 in FIG. 2 is sandwiched between the outer covering 14 andthe core 12 of the steering handle 10 for integrating the heater 16 withthe handle 10. Although various materials such as wood, polymericmaterials or the like may be used, the outer covering 14 is preferablyformed of leather, which may be sewn to itself for attaching thecovering 14 over the core 12 and the heater 16. In a preferredembodiment, a layer of two-way tape 80 is adhered (e.g., laminated) tothe separator 30 of the heater 16 with release paper (not shown) and thetape 80 is also adhered to the covering 14 of the steering handle 10 forassisting in securing the heater 16 to the covering 14. Preferably, thetape is applied to the heater 16 prior to shaping of the heater 16, butmay be applied thereafter. One exemplary two-way tape is sold under thetradename Duplotac 160 and is commercially available from LohmannTechnologies Corporation, 3000 Earhart Court, Suite 155, Hebran, Ky.41048. Thereafter, the covering 14 and heater 16 are preferably attachedtogether to the core 12 of the handle 10.

In an alternative preferred embodiment, the separator 30 may include anadhesive (e.g. an adhesive layer) on an outer surface 68 for assistingin securing the heater 16 to the covering 14. Preferably, the adhesiveis covered with release paper until it is applied (e.g. adhered) to thecovering 14. In both preferred embodiments, the separator 30 of theheater 16 is closer to the covering 14 than the cushion 26. It iscontemplated, however, that the tape may be applied to the separator 30and the separator 30 may be adhered closer to the core 12 than thecushion 26.

Advantageously, the separator 30, the cushion 26 or both, can assist inpreventing the conductor 24 from reading through the covering 14.Additionally, the separator 30, the cushion 26 or both, (e.g., whicheveris closest to the core 12) can assist in preventing heat loss to thecore 12 of the handle 10. Moreover, the separator 30, the cushion 26 orboth, (e.g., whichever is closest to the covering 14) can assist inallowing heat transfer to the covering 14 of the handle 10. It isfurther contemplated that the overall heater 16, once assembled, canstretch (i.e., elongate) at least about 5%, more preferably about 10%,even more preferably 15% and still more preferably about 20% of its ownlength prior to any significant damage or failure (e.g., rupture).Advantageously, when used, the zig-zag configuration of the conductiveelement 36 can assist in allowing the heater 16 to elongate whennecessary.

It is also contemplated that a control unit and one or more temperaturegauges may be employed with the heater of the present invention.Preferably, such a control unit is in signaling communication with thetemperature gauges associated with the heater and the control unitcontrols the amount of electricity supplied to the heater based upontemperatures sensed by the temperature gauges. In a preferredembodiment, the control unit employs pulse width modulation for loweringany temperature fluctuations exhibited by the heater. Of course this isonly one of many methods, which may be employed for maintaining orachieving a desired heat output from the heater.

Unless stated otherwise, dimensions and geometries of the variousstructures depicted herein are not intended to be restrictive of theinvention, and other dimensions or geometries are possible. Pluralstructural components can be provided by a single integrated structure.Alternatively, a single integrated structure might be divided intoseparate plural components. In addition, while a feature of the presentinvention may have been described in the context of only one of theillustrated embodiments, such feature may be combined with one or moreother features of other embodiments, for any given application. It willalso be appreciated from the above that the fabrication of the uniquestructures herein and the operation thereof also constitute methods inaccordance with the present invention.

The preferred embodiment of the present invention has been disclosed. Aperson of ordinary skill in the art would realize however, that certainmodifications would come within the teachings of this invention.Therefore, the following claims should be studied to determine the truescope and content of the invention.

What is claimed is:
 1. A handle, comprising: a core having asubstantially rigid portion; an outer covering that at least partiallycovers the core; a heater disposed at least partially between the coreand the outer covering, the heater including: i) a cushion configured asa layer; ii) a separator configured as a layer that is substantiallycoextensive with the cushion; and iii) a conductor at least partiallybetween the cushion and the separator wherein the conductor includesthree distinct zones, which form three separate circuits of a singularcontinuous conductive element and wherein a portion of the conductor isfolded over on itself and twisted at a connection of the heater.
 2. Ahandle as in claim 1, wherein the heater includes a plurality ofprotrusions corresponding to spokes of the handle.
 3. A handle as inclaim 1, wherein the conductor is in a lay-wire configuration betweenthe cushion and the separator and the cushion is formed of a compressedpolyurethane foam material.
 4. A handle as in claim 3, wherein at leastone zone of the three zones extends substantially parallel to anotherzone of the three zones.
 5. A handle as in claim 3, wherein theconductor is at least partially formed of strands that are formed of ametal alloy of copper and between about 1% and about 10% nickel.
 6. Ahandle as in claim 5, wherein the conductor includes about 5 to about 7strands and a diameter of each of the strands is between about 0.007 mmand about 0.011 mm.
 7. A handle as in claim 1, wherein the separator hasa heat transfer coefficient between about 0.10 W/m²K and about 2.0 W/m²Kand the cushion has a heat transfer coefficient between about 0.005 andabout 0.2 W/m²K.
 8. A handle as in claim 7, wherein the cushion iscloser to the core than the separator.
 9. A steering handle for atransportation vehicle, comprising: a core formed of a rigid member thatis at least partially covered with a polymeric material; an outercovering that substantially entirely covers the core; a heater disposedbetween the core and the outer covering, the heater including: i) acushion, the cushion being provided as a layer of foamed polymericmaterial having at least one elastomer; ii) an separator, the separatorbeing provided as a fabric layer that is substantially coextensive withthe cushion; and iii) a conductor at least partially between the cushionand the separator wherein the heater can elongate about 15% of its ownlength prior to any significant damage and wherein the conductorincludes three distinct zones, which form three separate circuits of asingular continuous conductive element and wherein a portion of theconductor is folded over on itself and twisted at a connection of theheater.
 10. A handle as in claim 9, wherein the heater includes aplurality of protrusions corresponding to spokes of the handle.
 11. Ahandle as in claim 9, wherein the conductor is in a lay-wireconfiguration between the cushion and the separator and the cushion isformed of a compressed polyurethane foam material.
 12. A handle as inclaim 9, wherein at least one zone of the three zones extendssubstantially parallel to another zone of the three zones.
 13. A handleas in claim 9, wherein the conductor is at least partially formed ofstrands that are formed of a metal alloy of copper and between about 1%and about 10% nickel.
 14. A handle as in claim 9, wherein the separatorhas a heat transfer coefficient between about 0.10 W/m²K and about 2.0W/m²K and the cushion has a heat transfer coefficient between about0.005 and about 0.2 W/m²K.
 15. A handle as in claim 9, wherein thecushion is closer to the core than the separator.
 16. A handle as inclaim 9, wherein the conductor includes about 5 to about 7 strands and adiameter of each of the strands is between about 0.007 mm and about0.011 mm.
 17. A steering wheel for an automotive vehicle, comprising: acore formed of a rigid member that is at least partially covered with apolymeric material, the core having a substantially circularconfiguration; an outer covering that substantially entirely covers thecore, the outer covering being formed of leather; a heater disposedsubstantially entirely between the core and the outer covering, theheater including: i) a cushion, the cushion being provided as a layer ofpolymeric material having at least one elastomer wherein the cushion isformed of compressed polyurethane, the cushion has a heat transfercoefficient between about 0.005 and about 0.2 W/m²K; ii) a separator,the separator being provided as a fleece layer that is substantiallycoextensive with the cushion, the separator being attached to thecushion with an adhesive wherein the separator has a heat transfercoefficient between about 0.10 W/m²K and about 2.0 W/m²K; and iii) aconductor substantially entirely between the cushion and the separator,the conductor being formed of one singular continuous conductive elementwherein the conductor is formed of a plurality of copper wire strandsthat are woven together, the conductor is separated into three distinctzones, which form three separate circuits that extend parallel to eachother in a zig-zag configuration and the strands are formed of a metalalloy of copper and between about 1% and about 10% nickel; wherein thecushion is closer to the core than the separator and a portion of theconductor is folded over on itself and twisted at a connection of theheater.
 18. A handle as in claim 1 wherein the heater can elongate about15% of its own length prior to any significant damage.
 19. A steeringwheel as in claim 1 wherein the material for the cushion has anelongation characteristic permitting it to be elongated at least about50% of its own length prior to failure.
 20. A steering wheel as in claim19 wherein the material for the separator has an elongationcharacteristic permitting it to be elongated at least about 50% of itsown length prior to failure.
 21. A steering wheel as in claim 17 whereinthe material for the cushion has an elongation characteristic permittingit to be elongated at least about 50% of its own length prior tofailure.
 22. A steering wheel as in claim 21 wherein the material forthe separator has an elongation characteristic permitting it to beelongated at least about 50% of its own length prior to failure.